New York Agricultural Experiment Station. 201 



chloroform in the normal way, except that the milk was pasteur- 

 ized at 85° C. (185° F.) and hydrochloric acid was used in the 

 place of lactic acid or a '' starter." In 55, rennet-extract alone 

 was used at the usual rate of 2.5 ounces for 1,000 pounds of milk. 

 In 56, in addition to rennet-extract, we added i gram of Parke, 

 Davis & Co.'s aseptic scale pepsin dissolved in water, and in 57, 

 we used 15 grams of the pepsin and the usual amount of rennet- 

 extract. We began tO' add the hydrochloric acid when the milk 

 was at 29.5° C. (85° F.), the additions being made in quantities of 

 5 cc. to 20 cc. at intervals, until the milk coagulated in 30 seconds 

 by the Monrad test. After the curd was cut, we added portions 

 of 20 cc. of hydrochloric acid at intervals of 5 to 15 minutes, 

 being guided by the general behavior of the curd. No salt was 

 added to the curd. In other respects, the method of manu- 

 facture was normal. The cheeses were ripened at 15.5° C. 

 (60° F.), and were analyzed at intervals. The detailed results 

 of tlie chemical work can be found iit the Appendix. In Table 

 IV, we give the analytical results found in the fresh cheese and 

 at the time of the last analysis. 



Table IV. — Showing Effect of Commercial Pepsin in Cheese-Ripening. 



In studying the results contained in Table IV, we notice: 



(i) The use of i gram of commercial pepsin in addition to 



